Aqueous compositions useful for stabilizing and texturizing dairy products and process for preparing the same

ABSTRACT

The present invention relates to a process for preparing an aqueous composition useful as a stabilizing and texturizing agent in dairy products, the composition obtainable by said process and a food composition comprising a dairy product base and said aqueous composition.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a process for preparing an aqueouscomposition useful as a stabilizing and texturizing agent in dairyproducts, the composition obtainable by said process and a foodcomposition comprising a dairy product base and the aqueous composition.

2. Description of the Related Art

In food industry, many dairy products such as soft white cheese areprocessed by heat-treatment, homogenization and hot-filling in order toobtain the packaged dairy product. If the heat-treatment or hot-fillingof the dairy product is carried out at temperatures of higher than 60°C., textural quality defects, such as a grainy, sandy or mealymouth-feel, may result due to uncontrolled protein agglomeration. Thisis a particular problem of low fat/high protein dairy productscontaining less than 10% fat due to a decreased stabilizing effect ofthe fat component. Although dairy products may be packaged in acold-fill process avoiding elevated temperatures, such cold-fillingrequires the use of an aseptic processing system.

It is known to use stabilizing compositions containing hydrocolloids andstarch in order to avoid syneresis in a dairy product, as described inWO 9957996, U.S. Pat. No. 5,614,243 and EP 289096. However, there isstill demand for a further improvement of such compositions, inparticular to be used in processing at elevated temperatures.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Therefore, it is an object of the present invention to provide a meansfor reducing or completely preventing uncontrolled protein agglomerationin protein-containing dairy products during heat-treatment orhot-filling, so that a dairy product can be produced combining theadvantages of a hot-fill process (shelf-life extension by 1 to 3 months)and a cold-fill process (high quality product texture) without beingforced to use an aseptic processing system.

This object is solved in the present invention by providing an aqueouscomposition comprising whey protein concentrate (WPC), starch, a firsthydrocolloid, and a second hydrocolloid, wherein the aqueous compositionhas been heated to a temperature in the range of 60-100° C. for a period(holding time) of 1 to 120 minutes.

Thus, in one aspect the present invention provides a process forpreparing an aqueous composition, which process comprises heating anaqueous mixture comprising 1.5 to 45 percent by weight (wt. %) of wheyprotein concentrate (WPC), calculated as WPC dry solids, 1 to 15 wt. %of starch, 0.15 to 6 wt. % of a first hydrocolloid, and 0.03 to 3 wt. %of a second hydrocolloid to a temperature in the range of 60 to 100° C.for a period of 1 to 120 minutes.

Preferably, the aqueous composition comprises 3 to 30 wt. % of WPC, morepreferably 5 to 25 wt. % and most preferably 10 to 20 wt. %. The wheyprotein concentrate may be any conventional product, and it may be inthe form of a liquid solution, dispersion or dried powder. In case thewhey protein concentrate is used in liquid form, its content in theaqueous composition is calculated on the basis of the dry WPC matter.Furthermore, if it is in liquid (aqueous) form, the aqueous content ofthe WPC may constitute all or part of the aqueous phase of thestabilizing composition.

The aqueous composition preferably comprises 1.5 to 10 wt. % of starch,more preferably 2.5 to 6 wt. %. Any starch or combinations thereof maybe used. Examples for suitable types of starch are waxy maize, corn,pea, wheat and potato.

The aqueous composition comprises a first hydrocolloid in an amount of0.15 to 6 wt. %, preferably 0.3 to 3 wt. % and more preferably 1 to 2.5wt. %. As the first hydrocolloid, a gum is preferably used. Any gumconventionally used in the field of food industry may be used, and thegum is preferably selected from one or more of carob bean gum (locustbean gum), guar gum, gum arabic, xanthan gum and tara bean gum. Morepreferably, the gum is carob bean gum.

The aqueous composition comprises a second hydrocolloid in an amount of0.03 to 3 wt. %, preferably 0.06 to 2.5 wt. %, more preferably 0.15 to1.5 wt. % and most preferably 0.3 to 1 wt. %. As the secondhydrocolloid, a gel-forming heteropolysaccharide is preferably used. Anygel-forming heteropolysaccharide conventionally used in the field offood industry may be used, and preferred examples are carrageenan andagar, more preferably carrageenan. A combination of one or moregel-forming heteropolysaccharides may be used.

In one particularly preferred embodiment, carob bean gum and carrageenanare used as the first and second hydrocolloid, respectively.

The aqueous composition comprises water in at least an amount necessaryto provide a slurry of the components mentioned above. Water constitutesthe remainder of the aqueous composition of the invention needed toaccomplish 100 wt. %. It is also possible to include additionalcomponents in the aqueous composition, such as texturizing andstabilizing components conventionally used in food industry. In thiscase, water also makes up the remainder of the aqueous compositionneeded to accomplish 100 wt. %.

In the process for preparing the aqueous composition of the presentinvention, a mixture comprising the components above and water is heatedto a temperature in the range of 60 to 100° C. for a period (holdingtime) of 1 to 120 minutes. Preferably, the heat-treatment is carried outat a temperature in the range of 70 to 95° C., more preferably 80 to 90°C. The duration of the heat-treatment is preferably 3 to 60 minutes,more preferably 5 to 30 minutes. The heat-treatment may be carried outunder atmospheric pressure or increased pressure.

The aqueous composition obtainable by the process of the presentinvention is useful as a stabilizing and/or texturizing agent dairyproducts. When used in such products, the aqueous composition canprevent uncontrolled protein agglomeration and, therefore, texturalquality defects such as a grainy, sandy and/or mealy mouth-feel. Inparticular, this effect is more prominent in a high protein dairyproduct. In this specification, the term “high protein” means a ratio ofprotein to fat of more than 1. Preferably, the dairy product is also alow fat dairy product. In this specification, the term “low fat” means afat content of less than 10 wt. % fat, based on the final product.Examples for dairy products wherein the aqueous composition in thepresent invention may be preferably used are yogurt, sour milk, creamcheese and soft white cheese.

In another aspect, the present invention provides a food compositioncomprising a dairy product base and the aqueous composition of thepresent invention. In the food composition of the present invention, thedairy product base is present in an amount of 30 to 80 wt. % and theaqueous composition is present in an amount of 70 to 20 wt. %, eachbased on the final food composition. Preferably, the content of dairyproduct base and aqueous composition in the food composition is 45 to 75wt. % and 55 to 25 wt. %, respectively, more preferably 60 to 70 wt. %and 40 to 30 wt. %, respectively.

Thus, the resulting food composition effectively comprises, in apreferred embodiment, 0.5 to 15 wt. % of WPC (calculated as dry matter),0.3 to 5 wt. % of starch, 0.05 to 2 wt. % of the first hydrocolloid and0.01 to 1 wt. % of the second hydrocolloid. More preferably, the foodcomposition comprises 1 to 10 wt. % of WPC, 0.5 to 3 wt. % of starch,0.1 to 1.0 wt. % of the first hydrocolloid and 0.02 to 0.8 wt. % of thesecond hydrocolloid. Even more preferably, the resulting foodcomposition comprises 2 to 8 wt. % of WPC, 0.8 to 2 wt. % of starch, 0.3to 0.8 wt. % of the first hydrocolloid and 0.05 to 0.5 wt. % of thesecond hydrocolloid.

Preferred dairy product bases to be used in the food compositionaccording to the invention are bases for yogurt, sour milk, cream cheeseand soft white cheese. In one preferred embodiment of the invention, alow fat and/or high protein dairy product base is used. It is possibleto use one or more dairy product bases in order to obtain desirablecharacteristics of the final dairy product. It is particularly preferredto use one or more soft white cheese bases for obtaining soft whitecheese, and more preferably to use one or more low fat/thigh proteinsoft white cheese bases. In the latter case, a desirable dairy producthaving a low fat content and high protein content while still providingexcellent textural quality (mouth-feel) may be obtained.

The prepared aqueous composition can be blended either batch wise orinline (continuously) into the protein-containing dairy product baseprior to final processing, e.g. heat-treatment, homogenization andhot-filling.

The resulting food composition exhibits improved texture and, therefore,mouth-feel, as no uncontrolled or undesired protein agglomeration occursduring processing, e.g. heat-treatment or hot-filling. This effect isparticularly prominent with low fat/high protein products such as lowfat/high protein soft white cheese which is conventionally subjected toa heat-treatment for sterilization and packaged by hot-filled requiringa temperature of more than 60° C. The hot-fill process results in ashelf-life extension, usually by 1 to 3 months, without being forced touse an aseptic processing system. Furthermore, when using the aqueouscomposition of the present invention in a dairy product, a similar oreven improved product quality, e.g. smooth product texture, as comparedto a cold-fill processing can be accomplished.

EXAMPLE

An aqueous composition was prepared by mixing together dried wheyprotein concentrate, starch, carob bean gum, carrageenan and water asset forth in the following table:

Percent by weight Percent by weight Component (in aqueous composition)(in food composition) WPC (dry) 14.6 4.8 Starch 6.1 2.0 Carob bean gum2.1 0.7 Carrageenan 1.2 0.4 Water 76 25.0 (from aqueous compositiononly)

The mixture was heated to a temperature of 95° C. for a holding time of15 minutes. Upon cooling, the aqueous composition was blended with lowfat/high protein soft white cheese base in an amount of 67 wt. % cheesebase and 33 wt. % aqueous composition, based on the resulting blend. Theblend was heat-treated at 55° C. for 2 minutes, homogenized andhot-filled at a temperature of 55° C. The resulting low fat/high proteinsoft white cheese exhibited a pleasant mouth-feel with no texturalquality defects and no occurrence of syneresis.

What is claimed is:
 1. A process for preparing an aqueous compositioncomprising heating an aqueous mixture to a temperature in the range ofabout 60 to about 100° C. for a period of about 1 to about 120 minutes,the aqueous mixture comprising about 1.5 to about 45 weight percent wheyprotein concentrate, calculated as dried product, about 1 to about 15weight percent starch, about 0.15 to about 6 weight percent of a firsthydrocolloid, and about 0.03 to about 3 weight percent of a secondhydrocolloid.
 2. The process according to claim 1, wherein the wheyprotein concentrate is in liquid or powder form.
 3. The processaccording to claim 1, wherein the starch is selected from the groupconsisting of waxy maize starch, corn starch, pea starch, wheat starchand potato starch, or combinations thereof.
 4. The process according toclaim 1, wherein the first hydrocolloid comprises one or more gums andthe second hydrocolloid comprises one or more gel-formingheteropolysaccharides.
 5. The process according to claim 4, wherein thegum is selected from the group consisting of carob bean gum, guar gum,gum arabic, xanthan gum and tara bean gum, or combinations thereof. 6.The process according to claim 4, wherein the gel-formingheteropolysaccharide further comprises carrageenan or agar, orcombinations thereof.
 7. The process according to claim 4, wherein theprocess is carried out under pressure.